Van Allen STEM Poster

Media

Music Video

Music Video by the Ionized Gases

Every second, a million tons of energized matter blasts off from the surface of Sun. Where does this “solar wind” go? Follow the speedy voyage of some protons, electrons and ions as they make a magnetic connection with Earth – becoming trapped in the Van Allen radiation belts that surround our planet. As they bounce, drift and spiral through the belts, some particles will shoot down Earth's long magnetic tail, while others spin back to the upper reaches of the magnetic field and spark the auroras – the amazing celestial light show we know as the northern (or southern) lights. Earth can be a crazy, magnetic place – watch this video to see how!

Student Reports

In April 2010, Maryland middle school students took part in a "Space Academy" session devoted to space weather and the Van Allen Probes. Hear what some of them had to say about Van Allen Probes and the chance to study Earth's radiation belts.

Draft Activities

Teachers: We would appreciate your feedback about the draft activities found in this section. If you would like to contribute to the pilot test phase, please try out the activities found here and provide feedback using the "Let Us Know What You Think- Pilot Test Questionnaire."

Math Problems by SpaceMath @ NASA

Students work with vectors to determine a spacecraft's orientation relative to Earth's magnetic field. They compute the expected strength of the magnetic field parallel and perpendicular to the spacecraft motion vector.

Topics: Graphing linear equations; equation of line perpendicular to another line; geometry

Students model spacecraft motion and the local magnetic field direction using two linear equations, then determine the line perpendicular to the spacecraft motion and the angle of motion relative to the magnetic field.

Students use the elliptical equation for the orbit of NASA's Van Allen Probes spacecraft, and a circle representing the location of the new Van Allen belt, to find where they intersect along the orbit of the spacecraft.

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EducationUseful Information

NASA's Living with a Star

Van Allen Probes is part of NASA's Living with a Star Program, a series of mission designed to gather critical information about the sun and its effects on Earth, and human activities, even other planetary systems.

Sun Earth Connections

We live in the extended atmosphere of the sun, an active star. While sunlight enables and sustains life, the sun's variability produces streams of low- and high-energy particles and radiation that can adversely affect life.

Under the protective shield of our magnetic field and atmosphere, Earth is an island in the solar system where life has developed and flourished. The fate of life on Earth is intimately connected to the way our planet responds to the sun's variations. Understanding the changing sun and its effects on life and society is a key area of study. Living With a Star addresses the effects of the sun's highly variable radiation and particle emissions on Earth.

Space Weather

We're all familiar with changing weather on Earth, but how many of us know "weather" also occurs in space? Just as it drives weather on Earth, the sun is responsible for disturbances in our space environment.

Besides emitting a continuous stream of plasma called the solar wind, the sun periodically blasts out billions of tons of matter in what are called coronal mass ejections. These immense clouds of material, when directed toward Earth, can cause large magnetic storms in our magnetosphere and upper atmosphere.

The term "space weather" generally refers to conditions on the sun, in the solar wind, and within Earth's magnetosphere and upper atmosphere that not only can influence the performance and reliability of technologies on the ground and in space, but can endanger human health or even life.

Missions

Living with a Star missions are addressing these crucial aspects of the relationship between sun and Earth.

The missions include the Solar Dynamics Observatory, which will study the solar atmosphere on small scales of space and time and in many wavelengths simultaneously; the Geospace-Van Allen Probes, which will will provide unprecedented insight into the physical dynamics of Earth's radiation belts; and Sentinels, designed to discover, understand and model the connection between solar phenomena and interplanetary disturbances.

Van Allen Probes Glossary

An alpha particle is a type of particle radiation that is made up of two protons and two neutrons bound together. It is identical to the nucleus of the element helium.

Aphelion

Aphelion is the point where a satellite (natural or human-made) is farthest from the sun in its orbit.

Apoapsis

Apoapsis is the point in an orbit when two objects are farthest apart. When they are closest together it is called periapsis.

Apogee

Apogee is the point in its orbit where a satellite (natural or human-made) is farthest from Earth.

Astronomical unit (AU)

An AU is the average distance from Earth to the sun, about 93 million miles, or 150 million kilometers.

Atmosphere

The atmosphere is the gas that surrounds a planet or star, and is held in place by gravity. Earth's atmosphere is mostly made up of nitrogen, while the sun's atmosphere consists mainly of hydrogen.

Axis

An axis is an imaginary line around which something rotates. The Earth’s axis for instance, passes through the north and south poles.

Conjunction

When two or more objects appear near one another in the sky, it is said that they are in conjunction.

Corona

The corona is the outermost part of a star’s atmosphere. The sun’s corona extends millions of kilometers from its surface with temperatures greater than a million degrees. This is fascinating to scientists because it would be expected that temperatures would drop as the distance from the sun’s core increases, yet the corona is about 200 times hotter than the surface.

Coronal Holes

Coronal holes are cooler and less dense areas in the sun’s corona, and they appear darker than surrounding regions. Fast-moving solar wind is known to come from coronal holes.

Coronal Mass Ejections

A coronal mass ejection, or CME, is a huge eruption on the surface of the sun that releases billions of tons of plasma with tremendous force. It is one of the biggest explosions in our solar system. The high-energy, high-speed particle radiation that is released during a CME can damage satellites, cause power outages on Earth, and create serious health concerns for astronauts.

Cosmic rays

Atomic nuclei (mostly protons) and electrons that crash into Earth's atmosphere with exceedingly high energies are called cosmic rays.

Cyclotron

A cyclotron is a circular machine that is used to accelerate charged particles to extremely high energies. It uses a magnetic field to bend the path of the particles so they move in a circle, repeatedly passing over plates whose charges switch back and forth from positive to negative—these alternating charges accelerate the particles. The high-energy particles collide with other particles, breaking them apart to reveal even smaller elementary particles within them.

Dipolar

The prefix “di-” means “two” or “double”, therefore dipolar means two or double poles. It refers to a magnetic field or electric field that has two equal and opposite points where the lines of force are most concentrated. Bar magnets, Earth, and the sun all have dipolar magnetic fields.

Density

Density refers to the amount of mass (“stuff”) in a certain space or volume. For example, an elevator with 12 people inside would have a greater density of people than the same elevator with only 2 passengers.

Electromagnetic radiation

Electromagnetic radiation or electromagnetic waves are produced by the motion of electrically charged particles. Radio waves, microwaves, visible light, and x-rays are all examples of electromagnetic radiation.

Electron

An electron is a negatively charged particle that orbits an atom’s nucleus. Electrons can be knocked out of their orbits through collisions with other particles or with electromagnetic radiation. Once free of their atoms, they can join other atoms or remain as free negative charges.

Electron volt (eV)

An electron volt is a unit of energy commonly used in particle physics. As an electron is pulled or pushed by Earth's magnetic field, its energy changes. We measure the amount of energy that an electron gains or loses in electron volts.

An electron volt is a very tiny unit (1.6 × 10-19 Joules). For large energy changes, scientists may use kilo-electron volts (keV) which are equal to 1000 electron volts, or mega-electron volts (MeV) which are equal to 1,000,000 electron volts.

Flux

Flux is how quickly a certain amount of something such as energy, particles, or a volume of fluid moves through a certain area in a certain amount of time. Flux also refers to the strength of a magnetic or electric field in a given area.

Geospace

The prefix “geo-” is from Greek and means “Earth,” therefore, geospace is the region of space that surrounds Earth. Geospace extends from Earth’s upper atmosphere to the limits of its magnetic field.

Geomagnetic storm

A geomagnetic storm is a disturbance in Earth’s magnetosphere, caused by a solar event such as a flare or coronal mass ejection.

Ion

An ion is an atom or group of atoms that have a positive or negative electric charge. If the atom gains an electron it becomes a negatively charged ion. If the atom loses an electron it becomes a positively charged ion.

Magnetic field

The area around an object or an electric current where magnetism can be detected is called the magnetic field. Like bar magnets, both Earth and the sun have dipolar magnetic fields. The Earth’s magnetic field is very important because it helps to shield us from the harsh solar wind, solar flares, and coronal mass ejections.

Magnetic field lines

Magnetic field lines show the structure of a magnetic field. To see the field lines of a magnet, place a piece of paper over a magnet, then sprinkle iron filings on the paper. The iron will line up along the magnetic field lines. If you could do the same to the entire planet, you would see a similar pattern of field lines.

Magnetometer

A magnetometer is an instrument that detects the strength and direction of magnetic force.

Magnetopause

The magnetopause is the boundary between Earth’s magnetosphere and the solar wind.

Magnetosphere

The magnetosphere is the area of space around Earth that is influenced by the planet’s magnetic field. It traps charged particles from the sun and carves out a protective space in the solar wind.

Magnetotail

The magnetotail is the part of the magnetosphere that is pushed away from Earth by the solar wind.

Matter

Matter is any substance that has mass and takes up space. Physical objects are composed of matter in the form of atoms, which are made up of smaller particles called protons, neutrons, and electrons.

Nucleus

The nucleus is the core of an atom. It is made of positively charged protons, and neutrons which have no charge. The nucleus makes up most of the mass of an atom.

Particle radiation

Particle radiation is energy given off by fast-moving subatomic (smaller than an atom) particles like electrons or protons. While particle radiation from space usually doesn’t reach Earth’s surface, it can be dangerous for astronauts and can damage satellites.

Periapsis

Periapsis is the point in an orbit when two objects are closest together. It is the opposite of apoapsis.

Perigee

Perigee is the point in its orbit where a satellite (natural or human-made) is closest to Earth.

Perihelion

Perihelion is the point in its orbit where a satellite (natural or human-made) is closest to the sun.

Plasma

Plasma is a fourth state of matter distinct from solid, liquid, or gas and is present in places such as stars and lightening. Plasma is made of free electrons and ions, (atoms that have an electric charge because they have lost or gained electrons). When enough energy is added to atoms, they can begin to move quickly and collide with one another with enough force to knock electrons free.

Proton

Protons are positively charged particles that, along with neutrons, form the core or nucleus of an atom. The number of protons in an atomic nucleus is what distinguishes one element from another.

Radiation

Radiation refers to energy in the form of particles or waves. Some examples of radiation include visible light and x-rays. See the definitions of “electromagnetic radiation” and “particle radiation” for more detailed information.

Radiation belts

The radiation belts are two donut-shaped regions encircling Earth where high-energy electrons and ions are trapped by Earth’s magnetic field. They are often referred to as the “Van Allen Belts” because they were discovered by James Van Allen and his team at the University of Iowa, in 1958.

Relativistic

Relativistic refers to something moving at a velocity approaching the speed of light.

Ring current

The electric current made up of electrons and ions that encircle Earth is known as the ring current. It flows clockwise around the equator when viewed from the north.

Satellite

An object that orbits around a larger astronomical object is a satellite. It can refer to a natural object such as a moon orbiting a planet, or it can refer to a human-made object, such as a spacecraft put into orbit around the Earth to relay communications signals or transmit scientific data.

Solar flare

A solar flare is a violent eruption in the sun’s atmosphere that heats plasma and sends large amounts of solar particles hurtling into space at tremendous speeds.

Solar minimum and maximum

The period when the sun is most active with solar flares, sun spots, and coronal mass ejections, is known as the solar maximum. The solar minimum occurs when the sun is least active. The sun’s activity level is on an 11-year cycle.

Solar wind

The solar wind is a constant stream of plasma flowing from the surface of the sun. Other stars have stellar winds too. The winds are strongest near the end of the star’s life, when it has consumed most of its fuel.

South Atlantic Anomaly (or SAA)

The SAA is a region over the South Atlantic Ocean where the inner Van Allen radiation belt comes closest to Earth's surface. The SAA is produced by a dip in Earth's magnetic field at that location. The excess energy in this region presents a problem for satellites whose orbits take them through it, exposing them to several minutes of strong radiation each time. The International Space Station required extra shielding to deal with this problem and the Hubble Space Telescope does not take observations while passing through this region.

Spectrum (plural - spectra)

In general terms, a spectrum is a continuous sequence or range of something. A familiar example of a spectrum of visible light is a rainbow.

Spectrometer

A spectrometer is a tool that is used to measure and record the spectrum, or range, of light (or sometimes particles) coming from a particular source.

Spectroscopy

Spectroscopy is the use of light to study matter. Light is emitted, reflected, or absorbed differently by different types of matter. Almost like a fingerprint, each type of matter has a signature pattern in the way it gives off, reflects, or absorbs light. By using a spectrometer to study the spectra or range of wavelengths of light, a scientist can learn something about an objects motion, composition, temperature, and more, even if they can’t examine the object up close. For example, spectroscopy might be used to study what elements are present in a star millions of kilometers away.

Vacuum

A vacuum is space that is empty, or nearly empty, of all matter.

Van Allen

Dr. James Van Allen and his team at the University of Iowa discovered the Earth’s radiation belts in 1958. This scientific discovery was a first for the space-age.